In methods of this kind, it is known to inject brine or other liquid into meat by using injection needles, which have to be inserted into the meat before injecting the liquid, and then removed again. The use of needles for this purpose is associated with many disadvantages, of which but a few may be mentioned, such as that the injection needles are costly; that the injection needles are easily broken if they are thin, and rupture or cut the meat fibres if they are thick; that the injection needles are difficult to clean and disinfect to the high standard required in food-processing apparatus; that the spacing of the injection points is set, usually permanently, by the spacing of the injection needles; and that no relative movement between the injection needles and the meat transverse to the longitudinal direction of the needles is possible, making it impossible to pass the meat at a constant speed through an injection unit.